The present invention concerns a method and an apparatus for the continuous feeding of fast printing machines, in particular the printing units of data processing centers that utilize supports or forms, joined as a continuous strip and folded in an accordion or fan-fold way.
The present invention thus relates to a method and an apparatus for the automatic or semi-automatic splicing of sheet material, particularly of forms made up as packages utilized in the feeding of data processing center printing machines that utilize "folded" forms or supports.
More specifically, the present invention concerns an apparatus for the automatic or semi-automatic splicing of packaged forms of the kind wherein the form has a predetermined configuration and hollow punching that, once printed and processed, will make envelope items (known also as pre-enveloped items) ready for mailing.
Typical specimens of said forms are the invoice or bills from general facilities, as those issued by electric or telephone companies etc. It is known that fast printing machines are fed with forms arranged into packages wherein the forms in question are united amongst themselves along two opposed margins and folded accordion like the ones on the others. Up to now, when a form package had been completely utilized by the machine, a new form package had to be provided and settled by the operator and the printing machine could thereupon restart operation.
In this manner, some inconveniences are experienced with modern fast printing machines, as hereinafter briefly described:
(a) dead times, that is the times required to insert a new form package for the printing machine feeding that amount to 25-30%, and in some instances to 50% of the time utilized by the machine to process a form package; PA1 (b) during the loading and insertion of a new form package the printing machine remains inactive and subjected to thermal and dynamic transients harmful to its correct operation.
Thus the operator is compelled to continuous and enervating attention and work, in that an absence of mind, even temporarly, on his part would result in very long dead times considering the times employed by a fast printing machine in utilizing and processing a single form package.
The main purpose of the present invention is that of doing away with the above problems and inconveniences and, in particular, of providing a method and apparatus that, even maintaining substantially unaltered the utilization of form conventional packages, wherein the single forms are already pre-printed and eventually arranged for the self-enveloping, will permit continuous feeding of the fast printing machine, thus eliminating the dead times in machine operation and hence, as a last result, of the data processing center. The specific scope of the present invention is to provide an apparatus for splicing in a semi-automatic manner the last form (that is the bottom form) of a package, in particular a form package already being fed to a printing unit, with the first form of another package.
A particular scope of the present invention is that of providing an apparatus having features as stated in the previous paragraph wherein the pre-formed die cut hollows of the forms are complied with and also the in-splicing-forms are utilizable without becoming scraps when processed by a fast printing unit. It will be evident, in effect, that a splicing inaccurately carried out, as it could be theoretically supposed, would imply the need to discard two forms (the last of a package and the first form of a successive one) with very remarkable complications within the printing unit cycle (especially if the unit is a laser or fast printing in character).